An endoscope is a medical-imaging device that may be used to examine the interior of a hollow organ or cavity of the body. Endoscopes may be used to provide visualization for non-invasive treatment of conditions within the nasal cavity and nasopharynx (among other places). For instance, an example of such treatment in the nasal cavity is disclosed in U.S. Pat. Pub. No. 2011/0004057, entitled “Systems and Methods for Transnasal Dilation of Passageways in the Ear, Nose, or Throat,” issued Feb. 4, 2010, the disclosure of which is incorporated by reference herein. An endoscope has an elongate body equipped with an imaging device for viewing of the treatment site within the patient. Some endoscopes are limited to a fixed viewing angle, however, a multi-angle endoscope is capable of a much broader range of viewing. A multi-angle endoscope is also capable of multiple viewing angles and rotation about the longitudinal axis of the elongate body. For instance, a multi-angle endoscope is disclosed in U.S. Pat. Pub. No. 2010/0030031, entitled “Swing Prism Endoscope,” issued Feb. 4, 2010, the disclosure of which is also incorporated by reference herein.
With such a wide capability of viewing, it may be confusing for the operator of a multi-angle endoscope to keep track of the exact viewing angle. Some endoscopes may be equipped with a means of determining the viewing angle; however, the operator may be required to look away from the endoscopic view displayed on a monitor in order to determine the viewing angle of the instrument. An endoscope operator may wish to determine the exact viewing angle without having to look away from the endoscopic view displayed on the monitor.
While several medical devices have been made and used, it is believed that no one prior to the inventors has made or used the invention described in the appended claims.
The drawings are not intended to be limiting in any way, and it is contemplated that various embodiments of the technology may be carried out in a variety of other ways, including those not necessarily depicted in the drawings. The accompanying drawings incorporated in and forming a part of the specification illustrate several aspects of the present technology, and together with the description serve to explain the principles of the technology; it being understood, however, that this technology is not limited to the precise arrangements shown.